linux_dsm_epyc7002/drivers/target
Xiubo Li b3743c71b7 tcmu: Fix possbile memory leak / OOPs when recalculating cmd base size
For all the entries allocated from the ring cmd area, the memory is
something like the stack memory, which will always reserve the old
data, so the entry->req.iov_bidi_cnt maybe none zero.

On some environments, the crash could be reproduce very easy and some
not. The following is the crash core trace as reported by Damien:

[  240.143969] CPU: 0 PID: 1285 Comm: iscsi_trx Not tainted 4.12.0-rc1+ #3
[  240.150607] Hardware name: ASUS All Series/H87-PRO, BIOS 2104 10/28/2014
[  240.157331] task: ffff8807de4f5800 task.stack: ffffc900047dc000
[  240.163270] RIP: 0010:memcpy_erms+0x6/0x10
[  240.167377] RSP: 0018:ffffc900047dfc68 EFLAGS: 00010202
[  240.172621] RAX: ffffc9065db85540 RBX: ffff8807f7980000 RCX: 0000000000000010
[  240.179771] RDX: 0000000000000010 RSI: ffff8807de574fe0 RDI: ffffc9065db85540
[  240.186930] RBP: ffffc900047dfd30 R08: ffff8807de41b000 R09: 0000000000000000
[  240.194088] R10: 0000000000000040 R11: ffff8807e9b726f0 R12: 00000006565726b0
[  240.201246] R13: ffffc90007612ea0 R14: 000000065657d540 R15: 0000000000000000
[  240.208397] FS:  0000000000000000(0000) GS:ffff88081fa00000(0000) knlGS:0000000000000000
[  240.216510] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  240.222280] CR2: ffffc9065db85540 CR3: 0000000001c0f000 CR4: 00000000001406f0
[  240.229430] Call Trace:
[  240.231887]  ? tcmu_queue_cmd+0x83c/0xa80
[  240.235916]  ? target_check_reservation+0xcd/0x6f0
[  240.240725]  __target_execute_cmd+0x27/0xa0
[  240.244918]  target_execute_cmd+0x232/0x2c0
[  240.249124]  ? __local_bh_enable_ip+0x64/0xa0
[  240.253499]  iscsit_execute_cmd+0x20d/0x270
[  240.257693]  iscsit_sequence_cmd+0x110/0x190
[  240.261985]  iscsit_get_rx_pdu+0x360/0xc80
[  240.267565]  ? iscsi_target_rx_thread+0x54/0xd0
[  240.273571]  iscsi_target_rx_thread+0x9a/0xd0
[  240.279413]  kthread+0x113/0x150
[  240.284120]  ? iscsi_target_tx_thread+0x1e0/0x1e0
[  240.290297]  ? kthread_create_on_node+0x40/0x40
[  240.296297]  ret_from_fork+0x2e/0x40
[  240.301332] Code: 90 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48
c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48
89 d1 <f3> a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38
[  240.321751] RIP: memcpy_erms+0x6/0x10 RSP: ffffc900047dfc68
[  240.328838] CR2: ffffc9065db85540
[  240.333667] ---[ end trace b7e5354cfb54d08b ]---

To fix this, just memset all the entry memory before using it, and
also to be more readable we adjust the bidi code.

Fixed: fe25cc34795(tcmu: Recalculate the tcmu_cmd size to save cmd area
		memories)
Reported-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Tested-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Reported-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Cc: <stable@vger.kernel.org> # 4.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-11 10:47:58 -07:00
..
iscsi target/iscsi: Remove dead code from iscsit_process_scsi_cmd() 2017-07-06 23:11:28 -07:00
loopback target/tcm_loop: Make TMF processing slightly faster 2017-07-06 23:11:25 -07:00
sbp sbp-target: Add an #include directive 2016-12-09 10:20:10 -08:00
tcm_fc Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2017-03-02 14:52:05 -08:00
Kconfig block: make scsi_request and scsi ioctl support optional 2017-01-31 10:53:05 -07:00
Makefile target: Put TCMU under a new config option 2015-04-19 22:41:12 -07:00
target_core_alua.c target: Use {get,put}_unaligned_be*() instead of open coding these functions 2017-07-06 22:57:59 -07:00
target_core_alua.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_configfs.c target: export lio pgr/alua support as device attr 2017-07-10 20:05:27 -07:00
target_core_device.c target: Fix cmd size for PR-OUT in passthrough_parse_cdb 2017-07-09 20:58:49 -07:00
target_core_fabric_configfs.c target/configfs: Kill se_lun->lun_link_magic 2017-06-08 23:26:38 -07:00
target_core_fabric_lib.c target: Use {get,put}_unaligned_be*() instead of open coding these functions 2017-07-06 22:57:59 -07:00
target_core_file.c target: break up free_device callback 2017-07-06 23:11:37 -07:00
target_core_file.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_hba.c target: Fix target_sense_desc_format NULL pointer dereference 2015-09-24 23:17:23 -07:00
target_core_iblock.c target: break up free_device callback 2017-07-06 23:11:37 -07:00
target_core_iblock.h target/iblock: convert iblock_req.pending from atomic_t to refcount_t 2017-05-01 22:20:43 -07:00
target_core_internal.h target: remove g_device_list 2017-07-06 23:11:41 -07:00
target_core_pr.c target: Fix return sense reason in target_scsi3_emulate_pr_out 2017-07-09 20:59:17 -07:00
target_core_pr.h target/pr: update PR out action code table 2017-05-01 22:20:44 -07:00
target_core_pscsi.c target: pscsi: Introduce TYPE_ZBC support 2017-07-06 23:11:49 -07:00
target_core_pscsi.h pscsi: finish cmd processing from pscsi_req_done 2017-07-06 23:11:46 -07:00
target_core_rd.c target: break up free_device callback 2017-07-06 23:11:37 -07:00
target_core_rd.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_sbc.c target: Use {get,put}_unaligned_be*() instead of open coding these functions 2017-07-06 22:57:59 -07:00
target_core_spc.c target: Fix cmd size for PR-OUT in passthrough_parse_cdb 2017-07-09 20:58:49 -07:00
target_core_stat.c target: Add counters for ABORT_TASK success + failure 2017-02-26 16:21:06 -08:00
target_core_tmr.c target: Introduce a function that shows the command state 2017-07-06 22:58:04 -07:00
target_core_tpg.c target/configfs: Kill se_lun->lun_link_magic 2017-06-08 23:26:38 -07:00
target_core_transport.c target: fix SAM_STAT_BUSY/TASK_SET_FULL handling 2017-07-06 23:11:48 -07:00
target_core_ua.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-07-04 14:13:43 -07:00
target_core_ua.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_user.c tcmu: Fix possbile memory leak / OOPs when recalculating cmd base size 2017-07-11 10:47:58 -07:00
target_core_xcopy.c xcopy: loop over devices using idr helper 2017-07-06 23:11:40 -07:00
target_core_xcopy.h target: check for XCOPY parameter truncation 2017-01-10 08:41:27 -08:00